The present invention relates generally to treatment of spinal discs, and more particularly to apparatus and methods for treating ruptured or degenerated spinal discs using a band of material wrapped around the spinal disc.
Various apparatus and methods have been suggested for treating spinal discs when they rupture, degenerate, or otherwise become injured. For example, spinal fixation, i.e., fixing the vertebrae on either side of an injured disc relative to one another, is a commonly used treatment. This may involve inserting pedicle screws or other anchors into the vertebrae, and securing rods, wires, plates, and the like between the vertebrae, thereby substantially removing much of the forces acting on the disc during subsequent activity by the patient. In addition, the injured disc may be removed and a fixation system used to anchor the adjacent vertebrae, while the vertebrae are fused to one another. Such fixation and fusion procedures, however, may substantially impair free movement by the patient, because relative movement of the vertebrae is intentionally fixed.
In addition to fixation, an injured disc may be completely removed and replaced with a prosthesis. Alternatively, a portion of a disc may be removed, and a prosthesis used to fill the resulting cavity, such as those disclosed in U.S. Pat. Nos. 5,549,679 and 5,571,189, issued to Kuslich. In a further alternative, xe2x80x9chybridxe2x80x9d material may be implanted directly within a space created within a spinal disc, as disclosed in U.S. Pat. No. 5,964,807, issued to Gan et al., rather than removing the entire disc.
Accordingly, apparatus and methods for treating spinal discs would be considered useful.
The present invention is directed to apparatus and methods for treating spinal discs, and more particularly to apparatus and methods for treating a ruptured or degenerated spinal disc using a band of material wrapped around the spinal disc.
In accordance with one aspect of the present invention, an apparatus is provided for treating a ruptured or degenerated spinal disc that includes a band of material. The band of material, which may be formed from biocompatible and/or bioabsorbable material, may have a length sufficient to wrap around an exterior of a spinal disc, and may have a width sufficient to cover a spinal disc and at least partially cover at least one vertebra adjacent the spinal disc. In addition, one or both ends of the band may include a connector, e.g., threads, clips, and the like, for securing the ends to one another or to another portion of the band.
The band may include healing-promoting material coated thereon, impregnated therein or otherwise carried thereby. For example, an extra-cellular matrix material may be carried on at least one side of the band of material. Optionally, at least a portion of the band may be electrically conductive, and a source of electrical energy may be coupled to the electrically conductive portion of the band.
Optionally, the apparatus may include an elongate member that includes a proximal end including a handle thereon, and a curved distal end including a connector element thereon. The band may include a first end that is releasably connectable to the connector element on the elongate member. In an exemplary embodiment, the connector element includes a hook on the distal end of the elongate member, and one end of the band includes an opening for receiving the hook therein.
In addition, the apparatus may include a fork member including proximal and distal ends defining an axis therebetween. The distal end may include a pair of tines, each tine including a transverse portion extending generally parallel to one another transversely with respect to the axis. The transverse portion of each tine may include a tip and a heel disposed proximal to the tip. A length between the tip and the heel may be sufficient for engaging a first vertebra with the tip and pivotally engaging a second vertebra with the heel to adjust a d stance between the first and second vertebrae.
In another embodiment, the apparatus may include a guide member including a proximal end and a curved distal end having a radius of curvature corresponding substantially to an exterior perimeter of a spinal disc. The guide member generally includes a lumen extending between the proximal and distal ends, the lumen having a size for receiving the band of material therethrough. Preferably, the lumen through the guide member is a slot including a height greater than a width of the band, the slot preferably having a height that extends substantially perpendicularly to the radius of curvature of the distal end. More preferably, the apparatus includes a pair of such guide members that are opposite hand from one another.
In accordance with another aspect of the present invention, a method is provided for treating a ruptured or degenerated spinal disc of a patient. Initially, an area adjacent an exterior of a spinal disc disposed between adjacent vertebrae is accessed. A band of material, such as that described above, may be wrapped around the disc to stabilize the disc in a desired position relative to surrounding anatomy. Preferably, the band engages at least one of the vertebrae when the band is wrapped around the disc to substantially secure the disc relative to the at least one of the vertebrae.
In one embodiment, this may involve extending a distal end of an elongate member along a first lateral region of the disc around a posterior region of the disc to an opposite second lateral region of the disc. A first end of the band may be connected to the distal end of the elongate member, and the elongate member may be pulled back around the posterior region of the disc, thereby directing the first end of the band around the posterior region of the disc. At least one of the first end and a second end of the band may be secured to another portion of the band, thereby securing the band around the disc.
In another embodiment, a tubular guide member may be inserted around a portion of the exterior of the disc, and the band may be inserted through the guide member to facilitate wrapping the band around a posterior region of the disc. Preferably, a pair of opposite-hand tubular guide members may be inserted around opposing lateral regions of the exterior of the disc. The band may be inserted directly through the guide members or may be directed through the guide members using an elongate member previously advanced through the guide members, which may be used to pull the band through the guide members.
Optionally, a location of at least one of the vertebrae may be adjusted relative to the disc before wrapping the band around the disc. For example, at least one of the vertebrae may be engaged between tines of a fork member, and the tines may be manipulated between the vertebrae to increase a space between the vertebrae. Alternatively, the patient may be subjected to traction.
If desired, an extra-cellular matrix material may be placed between the band and the disc, e.g., to promote healing of the disc. For example, one or more layers of extra-cellular matrix material may be carried on an interior surface of the band such that the extra-cellular matrix material is placed against the disc when the band is wrapped around the disc.
In addition, energy may be applied to the disc to enhance healing of the disc. For example, at least a portion of the band may be electrically conductive, and a source of electrical energy may be coupled to the electrically conductive portion of the band. Electrical energy may be applied to the disc via the electrically conductive portion of the band, or alternatively, energy may be applied directly to the disc, e.g., using a separate energy device.
In accordance with yet another aspect of the present invention, a method is provided for treating a spinal region of a patient. An area adjacent an anterior region of a spinal disc may be accessed, for example, by creating an incision in a ligament surrounding the disc to access an exterior of the disc. An instrument may be inserted between the ligament and the exterior of the disc, e.g., through the incision, in order to access a posterior region of the disc. A diagnostic or therapeutic procedure may be performed that involves accessing the posterior region of the disc.
For example, a tubular guide member may be inserted around a portion of the exterior of the disc, e.g., between the ligament and the disc until a distal end of the instrument is disposed adjacent the posterior region of the disc. One or more instruments may then be introduced through the tubular guide member to access the posterior region. For example, an imaging device, such as an endoscope, may be inserted through the guide member or directly between the ligament and the disc to the posterior region. The imaging device may be used to observe the posterior region and/or to otherwise assist in diagnosing a patient""s condition.
In addition to or instead of imaging, a therapeutic procedure may be performed at the posterior region of the disc. For example, a discectomy or other procedure may be performed that involves removing at least a portion of the disc from the posterior region, e.g., nucleus pulposus material that has leaked from within the disc. A therapeutic agent may be introduced into the posterior region or surrounding tissue to promote healing, pain relief, and the like. In addition, a band may be wrapped around the disc to stabilize the disc in a desired position relative to surrounding anatomy, as described above. In addition, tissue structures adjacent the posterior region of the disc, such as a facet joint or spinal cord, may be accessed from the posterior region to perform an intervention involving the accessed structure. Thus, the apparatus and methods of the present invention may provide a minimally invasive approach for accessing the posterior region of a spinal disc, while minimizing exposure of the disc and/or the spinal column adjacent the disc.
Other objects and features of the present invention will become apparent from consideration of the following description taken in conjunction with the accompanying drawings.